<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Flask if语句</title>
</head>
<body>
    <h3>Flask if语句</h3>
    {% if username == 'zhiliao' %}
        <p>zhiliao ketang</p>
    {% else %}
        <p>not zhiliao keteng</p>
    {% endif %}
    {% if age|int >= 18 %}
        <p>你可以去上网</p>
    {% else %}
        <p>未成年人不能上网</p>
    {% endif %}
</body>
</html>